Outbreaks of the porcine reproductive and respiratory syndrome (PRRS) virus seem to have slowed during the winter of 2013-2014, according to those monitoring the disease.

Steven Tousignant, DVM, with the National PRRS Incidence Project at the University of Minnesota, says the 2013-2014 PRRS epidemic season continues to be surprisingly different than previous seasons. Using the previous four years as a baseline to analyze for the expected number of breaks, he indicates that significantly fewer cumulative new PRRS breaks have been observed through December 2013 (p = 0.0002).

Fewer breaks were seen on a quarterly basis from both July to September (p = 0.0139), and from October to December (0.0049). Tousignant says the differences appearto have started back in the summer months.